diff --git a/test/zdtm/static/mnt_root_ext.c b/test/zdtm/static/mnt_root_ext.c
index 6a2eb068c..305e87262 100644
--- a/test/zdtm/static/mnt_root_ext.c
+++ b/test/zdtm/static/mnt_root_ext.c
@@ -51,6 +51,14 @@ int main(int argc, char **argv)
 		return 1;
 	}
 
+	/*
+	 * Make mounts in temporary mntns slave, to prevent propagation to criu mntns
+	 */
+	if (mount(NULL, "/", NULL, MS_SLAVE | MS_REC, NULL)) {
+		pr_perror("make rslave");
+		return 1;
+	}
+
 	/*
 	 * Populate to the tests root host's rootfs subdir
 	 */